1. Field of the Invention
This invention relates in general to ice making devices, and in particular to an ice making device that forms ice on a chilled vertical plate by running water down over the plate into a recirculating trough.
2. Description of the Prior Art
One type of ice making machine for commercial purposes uses vertical plates to form the ice. Each plate assembly consists of two plates which are welded at the periphery. Also, pattern welds are made at various points within the plates. Hydraulic pressure is applied between the plates to cause the plates to buckle outward and form passages between the plates for the passage of refrigerant.
A water distributor is mounted to one side of the plate at the top for distributing a stream of water over one side of the plate. The lower end of the plate extends into a trough for recirculating the water. Normally, two of the plates will extend into each trough. Each plate is bent so that the refrigerant portion is located on a vertical line outward of the edges of the trough. After the ice builds up on the outer sides of each plate assembly to a selected thickness, a warm refrigerant is circulated through to cause the sheet of ice to break loose and fall. Alternately, warm water is sprayed on the back side of the plate to warm the plate and release the ice. The ice falls vertically downward past the edge of the trough into a storage container.
While this type of ice making device is successful, one drawback is that each plate assembly forms ice only on one side of the plate assembly. One-half of the refrigerant surface of each plate assembly is wasted. One-half of the refrigerant surface of the plate assembly is exposed to ambient air between the two plate assemblies. This results in a loss of refrigerating energy because of heat infiltration into the space between the two plate assemblies.
Another type of ice making machine locates the vertical refrigerant portion directly above the trough. A deflecting grid is positioned above the trough and below the refrigerant portion. The deflecting grid has openings for the water stream to flow through. When the ice is released, the grid deflects the ice outward and down into a collection bin. In practice, the grids do not always work well. The impact of ice on the grid sometimes causes small pieces of ice to penetrate through the grid into the trough below. This is wasteful of usable ice production. Also, if the temperature of the supply water is low enough so that most of the ice particles penetrating the grid do not melt before the next ice harvest, then the ice below the grid will build up. This could block the flow of the recirculated water to the water pump or block the flow of the water through the grid, causing the water to flow out into the ice collecting chamber.
Movable deflectors are also used these devices are effective, but have the disadvantage of a mechanical movable device which is subject to malfunction.